FPGA-based Adaptive Phase-shift Compensation Method for Electronic Instrument Transformers

Abstract

Accurate and reliable instrument transformers play an important role in power system measurement and protection. This paper focuses on the phase accuracy of electronic instrument transformers and presents an adaptive phase-shift compensation method for measuring electronic current transformers. Different from the existing approaches in which the empirical evaluation and fixed phase-shift compensation are used, the proposed method measures the phase displacement in real-time and calibrates the corresponding phase error adaptively, with the aim of achieving high and reliable phase accuracy. In particular, several practical factors are considered in the design, such as the phase displacement composition, phase error uncertainty, synchronous mode diversity, and computational complexity and latency. The proposed method is developed in a field-programmable gate array platform with low-latency hardware implementation and further employed in a merging unit. Finally, the experimental results are provided to demonstrate the validity of the proposed method.

Keywords:

• electronic current transformer
• electronic voltage transformer
• merging unit
• phase accuracy
• phase-shift
• time delay
• calibration
• compensation
• IEC 60044-8
• IEC 61850

Acknowledgment

The authors would like to thank Mr. Yongxiang Shi and Mr. Liang Xu at the Experiment and Verification Center of State Grid Electric Power Research Institute, Nanjing, China, in providing technical support. The authors would also like to thank the editors and reviewers for their insightful comments and sincere suggestions on improving the quality of this work.

Additional information

Notes on contributors

Can Huang

Can Huang received his B.S. degree in electrical engineering from Hohai University, Nanjing, China, in 2008, and M.S. degree in electrical engineering from Southeast University, Nanjing, China, in 2011. His research interests include renewable energy, power systems, and power electronics.Contact information: Can Huang, School of Electrical Engineering, Southeast University, Nanjing, Jiangsu 210096, China.

Jun Mei

Jun Mei received his B.S. degree in radio engineering from Chongqing University, Chongqing, China, in 1994, and M.S. and Ph.D. degrees in electrical engineering from the Southeast University, Nanjing, China, in 2001 and 2006, respectively. He is currently an associate professor in the School of Electrical Engineering, Southeast University, Nanjing, China. His research interests include renewable energy, power electronics, power quality, and power system protection and automation.

Qiangsheng Bu

Qiangsheng Bu received his B.S. and M.S. degrees in electrical engineering from Southeast University, Nanjing, China, in 2006 and 2009, respectively. He is currently a Senior Engineer in State Grid Jiangsu Electric Power Company Research Institute, Nanjing, China. His research interests include smart substation, power system design and testing, and power system protection and automation.

Lin Su

Lin Su received his B.S. and M.S. degrees in electrical engineering from Southeast University, Nanjing, China, in 2002 and 2005, respectively. He is currently a deputy manager in China Energy Engineering Group Jiangsu Power Design Institute Co., Nanjing, China. His research interests include smart substation, power system planning and design, and power system protection and measurement.